Numerous tube or pipe couplings or fittings are known in the art, some of them which have quick connect and quick disconnect features. Examples are found in any patents, some typical ones being those noted here. U.S. Pat. No. 4,124,235 -Grahl et al., issued in November, 1978, is typical of a threaded body and nut arrangement having a wedge-like metal sleeve which is tightened in gripping relation with a tube extending therethrough as the nut is threaded on the external threads of the body. U.S. Pat. No. 1,615,233 to Redlinger, issued in January, 1927, is typical of some cantilever clamping action fittings using tapered threads to cause the Cantilever clamps to engage the pipe or other cylindrical member being gripped. U.S. Pat. No. 4,544,186 to Proni, issued in October of 1985, shows a similar clamp action fitting in which a fitting body has split ends provided with external threads. An internally threaded nut is threaded over the split ends. When the nut is threaded on the split ends until it bottoms out on a flange on the fitting body, the threads force the main body split ends into clamping engagement with a tube or pipe. U.S. Pat. No. 3,499,671 to Osborne, issued in March of 1970, shows another coupling for a tube without using flared ends, and includes a deformable metal sleeve between a nut and body having threaded engagement with each other.
It is typical of such prior art when threads or other camming surfaces are used that the threads or camming surfaces are exposed to contaminants or physical damage during handling and transport, as well as while being used as a coupling or connector. Others are not preassembled, and then attached to cylindrical members in clamping fashion without some disassembly or with only a minimum of securing action. Some do not provide adequate sealing arrangements to handle higher fluid pressures in the tubes or pipes which are connected by them.